Spring sash balance



Dec. 18, 1956 F. c. OSTEN SPRING SASH BALANCE Filed Feb. 8, 1954 ufi 2 J 0 2 LA 1 W I /4 i a Z L. IF m A w k L6 INVENTOR.

2719/ C Q's/e; BY @MWYW fl/IZS X wag United States Patent 2,714,119 SPRING SASH BALANCE Fred C. Osten, Detroit, Mich. Application February 8, 1954, Serial No. 408,939

7 Claims. 01. 230-52 This invention relates to builders hardware and, in particular, to sash balances.

' Gne object of this invention is to provide a spring sash balance which economizes on the space hitherto required for installation of the sash balance by enabling the sash balance to be housed entirely within the channel sash guide on each side of the window, instead of requiring separate space at the top of the window frarne.

Another object is to provide a spring sash balance mounted wholly within the channel sash guide and occupying the major part ofthe length of the sash guide, so that springs of great length can be used, with the result that a more even'balancing force is obtained than is possible devised have almost wholly replaced the sash weights, cords and pulleys previously used, because of the smaller amounts of space'required for spring sash balances than for sash weights and pulleys. In recent years, however, builders have complained that even these rotary drum spring sash balances occupy more space than can be conveniently allotted to them, as well as increasing the labor costs required in providing such space and in installing such sash balances. Spring sash balances hitherto developed for mounting in the side rails of the sashes themselves have been generally unsatisfactory because of the complicated mechanism required in accommodating such a sash balance in such a short vertical space, and the short spring to which such sash balances have been limited by the limited space available for housing them has resulted in the obtaining of a very uneven balancing force, as well as in the production of excessive friction. The same defects have arisen in sash balances of the block and tackle type employing multiple pulleys with multiple courses of sash tape or cord trained around these multiple pulleys in the short space available for them. This is true, Whethprovided with sufficient space within the sash guide to clear the. pulleys during operation of the sash balance.

Another object is to provide a spring sash balance mounted Wholly withinthe channel sash guide, so constructed and arranged that the mountingxscrews for the.

sash channel guides do not interfere with the working parts, of the sash balance in their vertical travel.

Another object is to provide a combination sash guide and balance whereinthe interior of the channel sash guide serves not only as a housing and guideway for the moving parts of the sash balance but also as a baclrbone forsus taining the pullof the balancing or tensioningspring. Another object is to provide a combination sash guide andbalance wherein the entire assembly is a single unit capable of being manufactured, sold and mounted as a single unit rather thanin separate units, thereby facilitating'mo'unting of the sash guide and balance and reducing the, cost of installation, r Qther'objects and advantages of the'invention will become'apparent during the'jburse of thevfollowing description of the accompanying drawings, wherein: 1 Figure l is a central vertical section through the sash balance according to one form of the present invention,

taken'along the-line ii'in Figure 2, with the upper portion bmitted, except for thej'ex'treme. upper end, in order to clonserv space; j i "1 e rigsr'ez is'a rear elevation of thesash guide and sash balari ce showh Figure 1, with the same portion omitted,

a ith certa flanges broken away to disclose the internal construction more clearly;

er the sash balance has been attemptedly housed Within a recess in the side rails of the sashes or in the side portions of the Window frame, because such prior installations have occupied only approximately one-half or less of the vertical height of the Window frame.

The sash balance of. the present invention solves these problems, and eliminates these difiiculties by housing the sash balance entirely within the channel metal side rails now increasingly used by builders in order to insure smooth opening and closing of the double-hung sliding sash used in the majority of dwellings constructed at the present day. The present sash balance utilizes the major portion of the length of the entire sash guide, hence requires only two pulleys for each sash balance and enables the use of springs of greater length than have hitherto, been capable of use, because of the limited length of space hitherto made available for such sash balances. The present sash balance consequently provides a more even balancing force over a longer rangeof travel of the sash than has hitherto been provided by spring sash balances, and, its parts. are so constructed andarranged that they are capable of passingone another during. their travel Within the channel sash guide as thesash moves upward or downward. The working parts of thepresent sash balance are also arranged in such a manner that the mounting screws for the sash guides, do not interfere in any way with the operation of the sash balance. Finally, the present invention enables the sash balance and sash guide to be manufactured, sold and mounted in a single unit, thereby reducing the amount ofskill of labor required and consequently reducingthe Eigure3is an enlarged horizontal crossrsection taken e1 e in 3+3 n F gu e h ughthe axle h urn pu y; an I j i figured is a horizontal cross-section talgen along the in in Figure} through thejaxle of the lower pulleyaSp'r g sash balancesfof the rotary 'drumtypefhitherto cost oi the installation. The sashbalance of the present invention requires no additional housing spacewithin the window frame or sash because it merely occupies space WhiCh iS already available in the interior of. t e channel metal sash guide regularly installed and required for the sash installation. a

Referring tothe drawingstimdetail, Figures l amil'Z show a combination sash; g'uide and sash balance, genera,

allyfdesignatedlfl, asacons'i-stinggenerally of a, channel sash guide 12 within whicl l is mounted the sashbalance i the present invention, The-sash guide 12, as showh .7 a

in, Figures 3. and 4, is. ofachannel construction 'withfia central rib 16.having central and lateral portions'18 and g I V ZOinteIcOnnectedby portions:212 perpendicularto the central and'laterallportions 1 d and 20 (Figure 4). integral with the. lateral portions. 20 .areparallel side portionsg t perpendicular. thereto and-the side portions 24 at their r'earwardedgee P O 1 t perpendi lar fl ges 26. 'lhe sashguide 12, of, which there is one omeach side of the window opening, is providedwith two oi; more (Figure 1 and 3) holes 28for receiving the mounting screws 30, the ends of which are lodged in the window frame side members V 4 side rails 46 with the central window pane 48 disposed lin T e t the central opening'thereof in the usual manner. side rails 46, only one of which is shown, are providedwith vertical grooves 50 for housing the sash balance tape 52, :stirrup 54 andanchorage'screw 56 (Figure l) without interference with the sash guide 12, in addition to the vertical grooves 57 regularlyiprovided for the sash guide ribs 16. The stirrup 54 is slotted as at 58 to receive the looped lower end of the sash tape 52, which is secured, after being doubled back on itself,- by a clip or clamp 60. The stirrup and the sash guide 12 are preferably of non- -ferrous metal, such as aluminum, in order to reduce corrosion and weathering, and the stirrup 54 is in the form of a tab having a hole 62 through which the anchoring .screw 56 passes on its way into the sash side rail 46.

springs 72 although shown with their upper portions omitted, along with the adjacent structure, are actually one foot or more in length, so that a long even pull is pro- 1 vided over a long range of travel upward or downward of Y V the sash 40.

The lower ends of the balance springs 72 are also tape connection plate 76. 'The latter is of approximately the internal width ofthe, sash guide 12 (Figure 2) and is slotted as at 7 8 to receive the upper; end of tthetsash balance tape 52, which, like the lower end thereof, is

hooked and pass through laterally-spaced holes 74 in a doubled over andisimilarly secured by a clip or clamp 80.

' such as metal or synthetic plastic, and is trained around lOWI and upper pulley units 82 and 8 4 respectively. The

V e The sash balance tape 52 i'sof 'strongefle'xible material '45 V outer end of said flexible, member;

pulley units 82and 84 consist of pulley brackets 86 and projects outwardtthrough' a'pair of aligned slots 102 and 104 in the pulley bracket 88"and sash guide central por 'tion 18 and the sash balance tape 52 passes outward over the pulley 100 through the same openings 102' and 104 The mounting of the upper-pn1ley'100 so that it lies within the ,slots 102 and 104 and projects'outwardly as ancing springs 72 spaced laterally apart fromfoneianothier places the springs 72 in locations where they passfon oppo: i

' E mountedjjwithin .said channel structure and depending "1 from said spring anchorage, lower, and upper'pulleys'rm tatably mounted ini verticallyspacedrelationship at ,sub-S stantiallyf stationary locations: said recess-within said p -shown in Figure 1 also provides space betweenlth e upper t .1 pulley 100 and the rear flanges'26. of the channel' sa sh guide 12 for thepassage offthebalancing springs-jl a'nd the tapejlconnection-plate 76'(Figure' 1),jso}thatl there is no interference between these parts during'thejoperaa tion ofjthe sash balance 14as thes'ash4t) is movedupwares: downward' Moreover, the use ofa pairof ibalsite .sides of the' upper pulley 71 00 .withoutlinterference therewith. ,athither consequence of j i t construction, thefasteners 301by whichthe combined unit1 0 is secured" to the-window name 'side niembers 32 pass through a cert:

7 tr'a'l space unoccupiedlby any 'moving rnechanism and consequefifly rw th i ite e sase n thtsu me h nism;

W lithe operation of the inventiomletrit be assumed that,

the combined sash guide and sashbalancelq hasbeen mounted in the manner shown in Figure 1, and that the sash balance tape stirrup 54 has been secured to an anchoring screw '56 at the bottom of the slot 50, with the sash in its raised or open position. If the operator wishes to close the window, he pulls the sash 40 downward in the usual Way, causing the sash balance tape 52 to be; pulled downward by its connection at the stirrup 54 to the;

upper pulleys 98 and to thetape connection plate 76," which travels downward past the upper pulley unit 84 without interference thereon, causing the balancing spring 72 to be stretched and placed under tension.

Theelongation ot the tensioning springs 72 in thist'rnanr ner causes potential energy to be stored up inithesprings' which counterbalances the weight of the sash 40., Consequently, when it is'desired to open the window, the raising of the sash 40 by'the operator is assisted by, the pull of the tensioned springs 72, transmitted through the sash balance tapes 52 on opposite sides of the sash 40 around the lower and upper pulleys 98 and 100 respectively.

What I claim isz V I t 1. A combination sash balance and hollow channel sash guide for an edge-grooved vertically-sliding window sash, comprising an elongated hollow channel structure includingahollow front'rib having an elongated recess 'in the back thereof, elongated front flanges extending laterally in opposite directions away from 'said rib, and

elongated side flanges extending rearwardly'taway from' said front-flanges, said Zrib guidingly engaging an edge groove of 'said 'sash in sliding relationship. 'therewith;

a sashttbalancing spring anchorage securedto the:upper portion of said channel'structure, balancing spring means, mountedtwithin said channel structure anddependingfrom-said spnng anchorage, lower and upper pulleys rotatablytmounted invertically-spaced relationship ,at'sub: stantially stationary locationsiinsaid recess withinlsaid rib, an elongated flexible tome-transmitting membersej- 1 cured at its'inner endrto said spring means and extending around saidpulleys outwardly through anop ening'in said rib, and a sash attachrnent elementjsecured to the, I, i"

A combination sash balance and hollowqchannel sash guide for an edge-grooved vertically-sliding window: 1'

sash; comprising an: elongated hollow channel; structure including. a hollow front rib v having an elongated" recess 1 ,in theflbacklthereof,elongated front 'fianges extendingt ,laterally inopposite directions, away from" said ribgland elongated side flanges extending rearwardly away from 7' said frontl fianges, said rib guidinglyengaging an', edge groovejof .saidisash in sliding relationship therewitm a sash I balancing spring 'anchorage gsecured to ;the:* upper portion of said channel structure, balaneingspringnieans rib, an, elongated. flexible force-transmitting 7 member ing around sa'id'pulleys outwardlythrgughi an opening? in said .rib, and-a f sash attachment elementsecured to the'outer end loffsaid zfiexible memben-one of said'piilleys I 7 being mounted'neanth'e' rnidportionof saidehannel stru'c fture'and thetother'pulley bingmounjt'e'din thelowerhalf 'ofisaid channel structure, J T

3. A combination sash balance and hollowjchann'el .sash guide for an edge-grooved verticallyrsliding' wlndow sash comprising an elongated hollow cha nhel structure" 1 including a hollow front ,lribghaving an elongated r' ees in the a k he eon: e ongated fr flt s' s t xt di s 1 laterally inopposite directions ,away'from said rib, and

" cnred'a't its'inni'fend tolsaid spring me'ans a'nd exten t i elongated side flanges extending rearwardly away from said front flanges, said rib guidingly engaging an edge groove of said sash in sliding relationship therewith; a sash balancing spring anchorage secured to the upper portion of said channel structure, balancing spring means mounted within said channel structure and depending from said spring anchorage, lower and upper pulleys rotatably mounted in vertically-spaced relationship at substantially stationary locations in said recess within said rib, an elongated flexible force-transmitting member secured at its inner end to said spring means, said flexible member extending downwardly from said spring means, around said lower pulley, then upwardly to and around said upper pulley and then outwardly through an opening in said rib, and a sash attachment element secured to the outer end of said flexible member.

4. A combination sash balance and hollow channel sash guide for an edge-grooved vertically-sliding window sash, comprising an elongated hollow channel structure including a hollow front rib having an elongated recess in the back thereof, elongated front flanges extending laterally in opposite directions away from said rib, and elongated side flanges extending rearwardly away from said front flanges, said rib guidingly engaging an edge groove of said sash in sliding relationship therewith; a sash balancing spring anchorage secured to the upper portion of said channel structure, a pair of balancing springs mounted within said channel structure in laterally-spaced relationship on opposite sides of the center line thereof and depending from said spring anchorage, lower and upper pulleys rotatably mounted in verticallyspaced relationship at substantially stationary locations in said recess within said rib, an elongated flexible forcetransmitting member secured at its inner end to said springs, said flexible member extending downwardly from said springs around said lower pulley, then upwardly to and around said upper pulley and then outwardly through an opening in said rib, and a sash attachment element secured to the outer end of said flexible member.

5. A combination sash balance and hollow channel sash guide for an edge-grooved vertically-sliding Window sash, comprising an elongated hollow channel structure including a hollow front rib having an elongated recess in the back thereof, elongated front flanges extending laterally in opposite directions away from said rib, and elongated side flanges extending rearwardly away from said front flanges, said rib guidingly engaging an edge groove of said sash in sliding relationship therewith; a sash balancing spring anchorage secured to the upper portion of said channel structure, a pair of balancing springs mounted within said channel structure in laterally-spaced relationship on opposite sides of the center line thereof and depending from said spring anchorage, a flexible force-transmitting member connector secured to and interconnecting the lower ends of said springs, lower and upper pulleys rotatably mounted in vertically-spaced relationship at substantially stationary locations in said recess within said rib, an elongated flexible force-transmitting member secured at its inner end to said connector, said flexible member extending downwardly from said springs around said lower pulley, then upwardly to and around said upper pulley and then outwardly through an opening in said rib, and a sash attachment element secured to the outer end of said flexible member.

6. A combination sash balance and hollow channel sash guide for an edge-grooved vertically-sliding window sash, comprising an elongated hollow channel structure including a hollow front rib having an elongated recess in the back thereof, elongated front flanges extending laterally in opposite directions away from said rib, and elongated side flanges extending rearwardly away from said front flanges, said rib guidingly engaging-an edge groove of said sash in sliding relationship therewith; a sash balancing spring anchorage secured to the upper portion of said channel structure, a pair of balancing springs mounted Within said channel structure in laterally-spaced relationship on opposite sides of the center line thereof and depending from said spring anchorage, a flexible force-transmitting member connector secured to and interconnecting the lower ends of said springs, lower and upper pulleys rotatably mounted in vertically-spaced relationship at substantially stationary locations in said recess within said rib, an elongated flexible force-transmitting member secured at its inner end to said connector and extending around said pulleys outwardly through an opening in said rib, and a sash attachment element secured to the outer end of said flexible member, said channel structure also including elongated rear flanges thereon extending laterally toward one another from said side flanges and forming longitudinal guides for said connector in its vertical travel within said channel structure.

7. A combination sash balance and hollow channel sash guide for an edge-grooved vertically-sliding window sash, comprising an elongated hollow channel structure including a hollow front rib having an elongated recess in the back thereof, elongated front flanges extending laterally in opposite directions away from said rib, and elongated side flanges extending rearwardly away from said front flanges, said rib guidingly engaging an edge groove of said sash in sliding relationship therewith; a sash balancing spring anchorage secured to the upper portion of said channel structure, a pair of balancing springs mounted within said channel structure in laterally-spaced relationship on opposite sides of the center line thereof and depending from said spring anchorage, a flexible force-transmitting member connector secured to and interconnecting the lower ends of said springs, lower and upper pulleys rotatably mounted in vertically-spaced relationship at substantially stationary locations in said recess within said rib, an elongated flexible force-transmitting member secured at its inner end to said connector and extending around said pulleys outwardly through an opening in said rib, and a sash attachment element secured to the outer end of said flexible member, said channel structure also including elongated rear flanges thereon extending laterally toward one another from said side flanges and forming longitudinal guides for said connector in its vertical travel within said channel structure, said side flanges and said rear flanges also cooperating with said front flanges to form a pair of elongated troughs facing one another, said springs being disposed in said troughs.

References Cited in the file of this patent UNITED STATES PATENTS 424,414 Forth Mar. 25, 1890 1,480,994 Church Jan. 15, 1924 2,284,438 Lundgren May 26, 1942 2,306,193 Stepan Dec. 22, 1942 

